Electrical connector with torsion contacts



Feb. 23, 1960 w. H. FLANAGAN, JR 2,926,328

ELECTRICAL CONNECTOR wm-x TORSION CONTACTS Filed Oct. 8. 1956 \NVENTOR. WILLIAM H. F'LANAGAN JR BYM l llrlll' ATIORNEY.

United States Patent ELECTRICAL CONNECTOR WITH TORSION CONTACTS William H. Flanagan, Jr., Wellesley, Mass, assignor to United-Carr Fastener Corporation, Boston, Mass, a corporation of Delaware Appiication October 8, 1956, Serial No. 614,442

2' Claims. (Cl. 339-192) This invention relates generally to. electrical connectors, and has particular reference to a connector which is adapted to receive and complete an electric circuit to a plurality of contact members.

In the construction of complicated electronic devices such as computers, it has been found convenient to utilize so-called printed wiring boards, on which conductors are formed in the desired configuration by chemical processes. To complete a circuit between such boards, or turn the board to an external source of power or to a controlled device, it is customary to run the printed circuits to the edge of the board, and provide a suitable connector with a plurality of contacts to make electrical connection therewith.

The design and manufacture of such connections has been a continuing problem. Due to space limitations, the contacts must be close together to accommodate as many circuits as possible. Hence the contacts must be as small as possible, yet must have sufficient resiliency to firmly engage the printed circuit board, to provide reliable connection thereto without permanent deformation, and in some cases must serve as the means for retaining the board in position.

Although several types of connectors for this purpose have been devised, each has certain disadvantages, such as not providing a reliable connection due to insufficient resiliency or not being capable of firmly retaining the board. Also, in most cases, the connectors are more bulky than is desirable, and are expensive to manufacture.

The object of this invention is to provide a connector for printed circuit boards which overcomes the above disadvantages, in that it provides, in a minimum of space a maximum number of contact members, which are so designed as to firmly grip the board to insure good electrical contact and to retain the board in position.

Another object of the invention is to provide a connector assembly in which contacts assembled therewith have pairs of contact portions which are held in abutting engagement by the connector body to receive a printed circuit board therebetween.

A further object of the invention is to provide a connector assembly in which contact members are provided which have contact portions separable by torsional flexing of resilient portions of the contact to receive a printed circuit board therebetween.

Other objects of the invention will be apparent to one skilled in the art from the following description of a specific embodiment of the invention.

In the drawing:

Fig. 1 is front plan view of a connector embodying the features of the invention;

Fig. 2 is a view in section taken on line 22 of Fig. 1;

Fig. 3 is a view in section taken on line 3-3 of Fig. 1;

Fig. 4 is a plan view of a contact member used in the assembly of Figs. l3; and

Fig. 5 is an end view of the contact of Fig. 4.

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Referring to the drawing, there is illustrated a con nector assembly 10 which is adapted] to receive and make electrical contact to a. printed, circuit board 12 having, conducting elements 14 on the surface thereof which extend to an edge of. the board.

The connector assembly 10 comprises generally an insulating body 16 having a series of contact members 18 assembled therewith. The body 16 has a number of. slots 20 formed in the front. face'22, a series of. spaced, apertures 24 in the bottom of. the slots which open to the rear face 25 of the body, and a series of. pairs of recesses 26 disposed in the walls of the slot, with, each. aperture having a pair of recesses associated therewith for a purpose to appear hereinafter.

The contact members 18' each comprise a retaining portion 28 disposed in an aperture 24 and protruding from the rear face 25 for receiving a. lead. wire. or. the like (not shown), a pair of flexible legs 30 extending from the retaining portion toward the front face of the body, and a contact portion 32 disposed on the free end of each leg 30.

The legs 30 are spaced apart and are disposed in the recesses 26 to enable the printed circuit board to enter therebetween. The contact portions 32 extend transversely from the ends of the legs and extend generally longitudinally in relation to the slot, and are inclined generally toward each other to abut in the center of the slot. The edges of the pairs of contact portions are rounded away from each other to facilitate entry of the board therebetween.

As illustrated in Figs. 4 and 5, prior to assembly into the body, the legs of the contact are spread apart. As the contact is assembled with the body by inserting the retaining portion into the slot from the front face of the body and through an aperture 24, the legs are flexed inwardly by engagement with the walls of the opposing recesses, so that the contact portions abut each other in lateral spaced relation to the axis of the arms.

Thereafter assembly of a printed circuit board into the slot causes the contact portions to separate and since the outermost edges thereof are confined by the recess walls, such separation is accomplished by torsional flexing of the legs rather than by outward bending thereof. The torsional flexing action provides a high contact pressure with a relatively small amount of movement of the contact portions, and such contact pressure is further enhanced by the fact that the contact portions are pressing tightly against each other prior to the insertion of the board therebetween.

Although in the illustrated embodiment the circuit continuing members are provided on only one face of the board, it will be understood that circuits may be provided on both sides if necessary. Provision may be made for any desired number of contacts in a slot, and any desired number of slots may be provided on the connector body.

Since certain other obvious changes may be made in the device without departure from the scope of the invention, it is intended that all matters contained herein be interpreted in an illustrative and not in a limiting sense.

I claim:

1. A connector assembly comprising an insulating body having a slot with a series of pairs of recesses disposed in the side walls, and a series of contact members assembled with the body, each of said contact members comprising a retaining portion at the bottom of the slot, a pair of spaced legs extending from the retaining portion in opposing recesses, and a pair of contact portions disposed at the ends of the legs, said contact portions having contacting surfaces spaced laterally from the axis of the legs, said contact portions extending generally longitudinally of the slot, and being inclined toward each other, the outermost edges thereof being engaged by the recessed walls and forced together so that said contact portions are contiguous with one another, said legs being joined to the contact portions in lateral spaced relation to the contiguous portions whereby operation of said contacting portions by insertion of a circuit-continuing device therebetween causes torsional flexing of said legs.

2. A connector assembly comprising an insulating body having at least one opening and one face, a series of spaced apertures in the bottom of said opening opening to an opposite face, and a pair of recesses associated with each aperture disposed in opposite side walls of said opening, and series of contact members assembled with the body, each of said contact members comprising a retaining portion disposed in an aperture, a pair of flexible legs extending from the retaining portion in the same general direction, said flexible legs being spaced apart and having contact portions extending from the flexible legs generally longitudinally in relation to said openings and in lateral spaced relation to one another with said contact tions flex apart by torsional flexing of the legs.

References Cited in the file of this patent UNITED STATES PATENTS 1,768,297 Schellenger June 24, 1930 2,154,301 Clement Apr. 11, 1939 2,154,302 Clement Apr. 11, 1939 2,543,000 Deakin Feb. 27, 1951 2,641,747 Johanson June 9, 1953 2,691,147 Sutton et al. Oct. 5, 1954 2,765,450 Richardson Oct. 2, 1956 

